This invention relates to a digital display system, more particularly to a display system in which an analogue input information is displayed digitally.
To make their use foolproof, recent photographic cameras are provided with means for automatically determining the degree of light exposure. For example such an automatic camera is provided with means for determining the shutter speed or the size of the opening of an irris diaphragm in accordance with information provided by a photoelectric conversion element, and means for displaying such conditions.
However, since known display means usually employ moviing coil type indicating meters, they are adversely effected by vibrations or shocks and their characteristics deteriorate with passing years so that the accuracy and stability of such prior art display means have not been satisfactory.
To solve these problems it has been proposed to incorporate a luminous element such as a luminous diode or a liquid crystal element in the finder of a camera. Although such elements are not affected by vibrations or shocks and can preserve the desired accuracy and stability because there is no movable element, they can operate only digitally. However, when the number of digits to be displayed increases it is difficult to dispose so many digits in a narrow space available in the finder. For example, the shutter speed is usually displayed in terms of 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2 and 1 sec. To dispaly this many shutter speeds, it is necessary to provide many display elememts, one for each speed, in the finder. It is not only difficult to install this many display elements in a narrow space but also necessary to use a large number of driving circuits, thus complicating the construction and increasing the cost of manufacture.